Technical Field of the Invention
The present invention relates to the cosmetic topical application of dehydroascorbic acid and monomeric derivatives, polymeric derivatives or isomers thereof, formulated into a composition comprising a physiologically acceptable medium, as an agent for artificially coloring the skin and, more particularly, as a skin self-tanning agent.
Description of Background and/or Related and/or Prior Art
Today, it is important to look healthy and a tanned skin is always a sign of good health. However, a natural tan is not always desirable since it requires long exposure to UV radiation, in particular to UV-A radiation that causes tanning of the skin but, however, is liable to induce an adverse change therein, in particular in the case of sensitive skin or of skin that is continually exposed to solar radiation. It is thus desirable to find an alternative to a natural tan that is compatible with the requirements of such skin types.
Most of the cosmetic products intended for artificially tanning the skin are based on carbonyl derivatives which, by interacting with the free amine functions of the skin, in particular the amino acids, peptides or proteins of the skin, allow the formation of colored species.
To this end, it is known that dihydroxyacetone, or DHA, is a particularly advantageous compound which is commonly employed in cosmetics as an agent for artificially tanning the skin; when applied to the skin, in particular to the face, it gives a tanning or bronzing effect which is similar in appearance to that which may result from prolonged exposure to sunlight (a natural tan) or under a UV lamp.
One drawback of DHA is the length of time the coloration takes to develop: specifically, several hours (3 to 5 hours in general) are required for the coloration to be revealed. Another drawback of DHA is its tendency to produce yellow shades that harm the production of a natural skin tone. There is thus increasing demand for self-tanning products that act quickly and provide a coloration closer to that of a natural tan.
Thus, need continues for novel compounds and novel compositions that can give the skin an artificial coloration close to that of a natural tan in a simple, effective and fast manner.
WO 2005/039 510 discloses the use of dehydroascorbic acid or a salt thereof produced in situ via enzymatic oxidation, as a fixing agent in the permanent waving of hair. DE-197,45,354 also discloses the use of dehydroascorbic acid in combination with particular compounds with primary or secondary amine groups or hydroxyl groups, for coloring the hair.